Complex Multiplier Design Example v1.0.0 README File


This readme file contains the following sections:

o  Package Contents
o  Tool Requirements
o  Description of Design Example
o  Simulation in Simulink
o  Release History
o  Design Examples Disclaimer
o  Contacting Altera



Package Contents
================

Complex Multiplier Design Example v1.0.0
Design files include:
	o complex_mult_C_DA_reloadable_coef_MEM.mdl - DSP Builder design file implementing 18x18 complex multiplier
          with reloadable coefficients
	o init.m - MATLAB script to initialize the sampling time, simulation time and coefficient value
	o compute_partial_product.m - MATLAB script to calculate the partial products based on the initial coefificient
	  value set in init.m.  Two sets of partial products are calculated for each coefficient value: one for the
          MSB segment and the other for the LSB segment of the data.  Since the design uses the canonical representation,
          in addtion to the partial products for the real coefficient, Cr, and imaginary coefficient, Ci, the partial products 
	  for Cr - Ci is also precomputed.
	o complex_mul.m - MATLAB script to verify the simulation results in Simulink


Tool Requirements
=================

This design example requires the following software package:
	o Quartus II 5.0
	o DSP Builder v5.0.0
	o MATLAB/Simulink R14 SP2
	 
Please contact your local sales representative if you do not have one of these
software tools.



Description of Design Example
=============================

This is a 18x18 complex multiplier implemented using the distirbuted arithmetic (DA) which is implemented using the M4K
TriMatrix memory blocks.  The coefficients are reloadblae.  

It uses the canonical representation requiring 3 multipliers, 3 adders and 2 subtractors:

D = Dr + j*Di  { Data }
C = Cr + j*Ci  { Coefficient }
R = D*C = Rr + j*Ri  { Result }
Rr = Dr*Cr – Di*Ci 	{same as conventional representation}
Rr = Dr*Cr – Di*Ci + (Dr*Ci - Di*Cr) - (Dr*Ci - Di*Cr)
Rr = (Dr*Cr – Dr*Ci + Di*Cr - Di*Ci) + (Dr*Ci - Di*Cr)

Rr = ((Dr + Di)*(Cr - Ci)) + (Dr*Ci - Di*Cr)
Ri = Dr*Ci + Di*Cr 		{same as conventional representation}

The coefficient is implemented as partial products in the M4K TriMatrix memory blocks.  The M4K memory blocks
are configured as dual-port RAMs and can store two sets of coefficients.  To choose which coefficient set
to use, set the coef_set bit appropriately.  

The coefficient is also reloadable while the multiplication operation takes place.  It will automatically reload
into the coefficient set which is not being used.  To reload a new coefficient, assert the coef_reload
bit and keep it asserted throughout the entire reload period.  The partial product for the coefficient needs to be
precomputed.  Refer to the compute_partial_product.m script for details.


To get more details on the discrete blocks in DSP Builder, refer to the DSP Builder Reference Manual 
located at:

http://www.altera.com/literature/manual/mnl_dsp_builder.pdf

To get more details on the soft multipliers (DA using TriMatrix Memory Blocks), refer to
AN 306: Techniques for Implementing Multipliers in Stratix, Stratix GX, and Cyclone Devices
located at:

http://www.altera.com/literature/an/an306.pdf




Simulation in Simulink
======================

To run the simulation of the design example in Simulink, perform the following steps:
1.  Open the complex_mult_C_DA_reloadable_coef_MEM.mdl file.
2.  To review the simulation parameters, select "Configuration Parameters" (Simulation menu).  The Stop Time
    is set by the variable "simtime", initialized in the init.m file.
3.  To start simulation, select "Start" (Simulation menu).  

At the end of simulation, the design runs a MATLAB script: complex_mul.m to verify if the simulation results
are correct.  If they are, it will generate a "Passed" message in the MATLAB workspace with the number of 
simulation data compared.  Otherwise, it will generate a "Fail" message.


To get more details on the design flow using DSP Builder, refer to the DSP Builder User Guide 
located at:

http://www.altera.com/literature/ug/ug_dsp_builder.pdf



Release History
===============

Version 1.0.0
-------------

Initial release  



Design Examples Disclaimer
==========================

These design examples may only be used within Altera Corporation devices and remain 
the property of Altera. They are being provided on an “as-is” basis and as an accommodation; 
therefore, all warranties, representations, or guarantees of any kind (whether express, 
implied, or statutory) including, without limitation, warranties of merchantability, non-infringement, 
or fitness for a particular purpose, are specifically disclaimed. Altera expressly does not recommend, 
suggest, or require that these examples be used in combination with any other product not provided 
by Altera.



Contacting Altera
=================

Although we have made every effort to ensure that this design example works 
correctly, there might be problems that we have not encountered. If you have 
a question or problem that is not answered by the information provided in this 
readme file or the example's documentation, please contact your Altera Field 
Applications Engineer.

If you have additional questions that are not answered in the documentation
provided with this function, please contact Altera Applications:

World-Wide Web:                 http://www.altera.com
                                http://www.altera.com/mysupport/
Technical Support Hotline:	(800) 800-EPLD (U.S.)
                                (408) 544-7000 (Internationally)
                                
Copyright (c) 2005 Altera Corporation. All rights reserved.